What tool to measure SWR at 910 Mhz?
 

What tool would one use to measure the SWR at 900Mhz?

I've never seen swr bridges that went that high.

A specific model number and source would be helpful...


Paul (Kl7JG)

On Sat, 07 May 2005 16:14:15 -0700, wrote:

What tool would one use to measure the SWR at 900Mhz?

I've never seen swr bridges that went that high.

A specific model number and source would be helpful...


Paul (Kl7JG)



The manual for my Bird 43 watt meter says it is rated for service up
to 2300 Mhz. I've used it up to the 440 Mhz range with no problem.

One Bird source is http://www.rfparts.com/

Another, with both new and used Birds is http://www.radiodan.com/

bob
k5qwg

Paul:

How far away is the electronics lab from the rocket lab--on campus?

Those guys might be friendly there... grin

Warmest regards,
John

"Bob Miller" wrote in message
...
| On Sat, 07 May 2005 16:14:15 -0700, wrote:
|
| What tool would one use to measure the SWR at 900Mhz?
|
| I've never seen swr bridges that went that high.
|
| A specific model number and source would be helpful...
|
|
| Paul (Kl7JG)
|
|
|
| The manual for my Bird 43 watt meter says it is rated for service up
| to 2300 Mhz. I've used it up to the 440 Mhz range with no problem.
|
| One Bird source is http://www.rfparts.com/
|
| Another, with both new and used Birds is http://www.radiodan.com/
|
| bob
| k5qwg
|
|
|

On Sun, 08 May 2005 00:19:04 GMT, Bob Miller
wrote:

On Sat, 07 May 2005 16:14:15 -0700, wrote:

What tool would one use to measure the SWR at 900Mhz?

I've never seen swr bridges that went that high.

A specific model number and source would be helpful...


Paul (Kl7JG)



The manual for my Bird 43 watt meter says it is rated for service up
to 2300 Mhz. I've used it up to the 440 Mhz range with no problem.

One Bird source is http://www.rfparts.com/

Another, with both new and used Birds is http://www.radiodan.com/

The problem with the Bird is that it requires considerable power to
run it. With 1 watt available, you're (the OP) kind of out of luck.

The OP has access to a spectrum analyzer/tracking generator. I
suggest a directional coupler with the main arm driven by the
generator, the coupled arm as the input to the SA and the thru port to
the DUT. Calibrate the SA with a short on the output of the coupler
(100% reflection) and measure return loss directly in dB on the
screen.

A similar idea using diode detection is he

http://www.qsl.net/n9zia/24swr/

A Wattmeter is probably the easiest to use at 910. Slugs for the
standard Bird Wattmeter can be bought to cover that range. At work, I
use a Telewave Wattmeter. It goes from 20 to 1000 MHz with no slugs.
The model 44A is probably the best bang for the buck (in my opinion).

http://www.telewave.com/pricelist/wattmeter.html

For the Bird (4410A Wattmeter):
http://www.bird-electronic.com/produ...ct.aspx?id=333

Scott
N0EDV

wrote:

What tool would one use to measure the SWR at 900Mhz?

I've never seen swr bridges that went that high.

A specific model number and source would be helpful...


Paul (Kl7JG)

On Sun, 08 May 2005 06:54:50 -0700, Wes Stewart
wrote:

On Sun, 08 May 2005 00:19:04 GMT, Bob Miller
wrote:

On Sat, 07 May 2005 16:14:15 -0700, wrote:

What tool would one use to measure the SWR at 900Mhz?

I've never seen swr bridges that went that high.

A specific model number and source would be helpful...


Paul (Kl7JG)



The manual for my Bird 43 watt meter says it is rated for service up
to 2300 Mhz. I've used it up to the 440 Mhz range with no problem.

One Bird source is http://www.rfparts.com/

Another, with both new and used Birds is http://www.radiodan.com/

The problem with the Bird is that it requires considerable power to
run it. With 1 watt available, you're (the OP) kind of out of luck.

Bird does have a 1-watt measuring element, part 800-1, for 800-950 Mhz
-- there's also a 2.5 watts element, the 800-2.

Still, this is all may a bit pricey, about $4-500 for the meter and
one element -- maybe he can borrow?

bob
k5qwg



The OP has access to a spectrum analyzer/tracking generator. I
suggest a directional coupler with the main arm driven by the
generator, the coupled arm as the input to the SA and the thru port to
the DUT. Calibrate the SA with a short on the output of the coupler
(100% reflection) and measure return loss directly in dB on the
screen.

A similar idea using diode detection is he

http://www.qsl.net/n9zia/24swr/

A "cheap fix" would be a FWD-REF takeoff bridge--SD's colleges' electronic
lab/engineering surely must have a SHF oscilliscope--or the students able to
slap together a decade freq divider to put before a slower scope...

John
--
When Viagra fails to work--you are DOOMED!!!

"Bob Miller" wrote in message
...
| On Sun, 08 May 2005 06:54:50 -0700, Wes Stewart
| wrote:
|
| On Sun, 08 May 2005 00:19:04 GMT, Bob Miller
| wrote:
|
| On Sat, 07 May 2005 16:14:15 -0700, wrote:
|
| What tool would one use to measure the SWR at 900Mhz?
|
| I've never seen swr bridges that went that high.
|
| A specific model number and source would be helpful...
|
|
| Paul (Kl7JG)
|
|
|
| The manual for my Bird 43 watt meter says it is rated for service up
| to 2300 Mhz. I've used it up to the 440 Mhz range with no problem.
|
| One Bird source is http://www.rfparts.com/
|
| Another, with both new and used Birds is http://www.radiodan.com/
|
| The problem with the Bird is that it requires considerable power to
| run it. With 1 watt available, you're (the OP) kind of out of luck.
|
| Bird does have a 1-watt measuring element, part 800-1, for 800-950 Mhz
| -- there's also a 2.5 watts element, the 800-2.
|
| Still, this is all may a bit pricey, about $4-500 for the meter and
| one element -- maybe he can borrow?
|
| bob
| k5qwg
|
|
|
| The OP has access to a spectrum analyzer/tracking generator. I
| suggest a directional coupler with the main arm driven by the
| generator, the coupled arm as the input to the SA and the thru port to
| the DUT. Calibrate the SA with a short on the output of the coupler
| (100% reflection) and measure return loss directly in dB on the
| screen.
|
| A similar idea using diode detection is he
|
| http://www.qsl.net/n9zia/24swr/
|
|

On Sun, 08 May 2005 15:18:06 GMT, Bob Miller
wrote:

Bird does have a 1-watt measuring element, part 800-1, for 800-950 Mhz
-- there's also a 2.5 watts element, the 800-2.

I stand corrected. I just checked the RF Parts link and didn't see
any.

Thanks for all of the replies.
I just ordered a used Bird 43 and an 801-1 1W 800-1000Mhz element.
from radiodan.

Paul (KL7JG)

Also, any of the Bird lookalikes (Struthers, Dielectric, STB,
General Signal, ect. ) These are almost duplicates of the Bird 43
even use the same slugs, and their slugs will work in Bird meters)
Also, Struthers, ect. made meters that have 4 power range slugs
(good to 500 watts, and 1000 MHz) Telwave (no slugs required, has
4 range power switch, looks otherwise a lot like the #43) is good
to 1000 MHz. Can find them on E-BAY, under
"Watt Meters". As info, Jim NN7K


Bob Miller wrote:
On Sat, 07 May 2005 16:14:15 -0700, wrote:


What tool would one use to measure the SWR at 900Mhz?

I've never seen swr bridges that went that high.

A specific model number and source would be helpful...


Paul (Kl7JG)




The manual for my Bird 43 watt meter says it is rated for service up
to 2300 Mhz. I've used it up to the 440 Mhz range with no problem.

One Bird source is http://www.rfparts.com/

Another, with both new and used Birds is http://www.radiodan.com/

bob
k5qwg

wrote in message
...
Thanks for all of the replies.
I just ordered a used Bird 43 and an 801-1 1W 800-1000Mhz element.
from radiodan.

Paul (KL7JG)



Uh-oh!! You're in trouble now. As a recovering Bird addict, I must warn
you that YOU CAN'T OWN JUST ONE BIRD SLUG.

You ordered a 1-watt 800-1,000 Mhz element and you think you're safe. No
way. You will notice that the Bird carrying case has room for several
slugs, so why not fill it up? So, you'll figure, oh, what the hell, I
really need a 1KW HF slug. Then comes a 1-watt HF slug. Then maybe you'll
need a 100-watt VHF slug. And from that point on, it's all downhill into
the dark night of addiction.

Then your wife says, "Why do you need all these?" And you say something
like, "Well, I have half as many slugs as you have shoes so what's the
problem."

Get help, quick!!!

I know.

:-)


--

-----
Joe S.

my avair meter goes up to 5 gig
so shove hand in pocket and buy one
about £200
tight wad

"yammyr6" wrote in message
...
my avair meter goes up to 5 gig
so shove hand in pocket and buy one
about £200
tight wad


Or you could get back to basics. Buy a used directional coupler off of eBay.
Measure power forward & reverse, and do the simple math.

--
Ed
WB6WSN
El Cajon, CA USA

Or get even further back to basics and MAKE a directional coupler.
It's not all that difficult, and not bad to check for directionality.
RFSim99 has a tool for designing microstrip and other couplers (though
it fails to tell you that for the given coupling, the microstrip lines
should be coupled for a quarter wave distance). Hint: people who
manufacture equipment that operates in the GHz region often put
couplers right on the PC boards--biggest cost is a bit of real estate.

Cheers,
Tom

On 10 May 2005 10:15:02 -0700, "K7ITM" wrote:

Or get even further back to basics and MAKE a directional coupler.
It's not all that difficult, and not bad to check for directionality.
RFSim99 has a tool for designing microstrip and other couplers (though
it fails to tell you that for the given coupling, the microstrip lines
should be coupled for a quarter wave distance). Hint: people who
manufacture equipment that operates in the GHz region often put
couplers right on the PC boards--biggest cost is a bit of real estate.

Or rip one out of a defunct cell phone.


Wes